Brake



May 21, 1935. H. F. PARKER BRAKE Filed July 26', 1929 46 INVENTOR y wmp/:rg I.' 19M/eer. BY 4 '-ZS-J i Afrox EY Patented May 21, 1935 y f m/ UNITED STA-TES PATENT OFFICE] BRAKE -Humphrey' F. Parker, SouthBend, Ind., assigner i to Bendix Brake Company, South Bend, Ind.,

a corporation of Illinois Application July 26, 1929, Serial No. 381,195 1 Claim. '(01. iss- 78) This invention relates to brakes and is illus-Y Figure 2 is a section taken on the line 2-2 trated as embodied `in an internal expanding of Figure 1 through the novel tension link anchor automobile brake of the type having one part structure;

l which anchors when the drumis turning in one Figure 3 is a partial section throughfthe brake 15 direction and a different` part 'which anchors applying means taken onrthe line 3-3 of Fig- 5 when thel-drum'is turning in the other direction.` ure 1; and.

The invention is furthermore directed to a full Figure 4:v is a section" taken on the line 4'-4 Wrapping brake, that' is one wherein practically of Figure 1 disclosing the novel combined steady 360iA of 1 brake lining contact thevro-tating drum, rest and guide.

Ybeing wedged into engagement therewith by the The illustrated brake includes a rotatable drum 10l wiping effectief the drum augmented by the aci8 at the open side of which" is a support such as tion of the cam or other applyingmeans.V l a backingplate i2 and Within which is arranged With brakes of this type it is the practice to the friction means of the brake. This frictionprovide a considerable lining clearance `in the means preferably includes a pair of novel inter-4,

`release position and when the torque is taken at changeable shoes I4 and iE and transverse pivots 15 the ends of the brake, as is disclosed in my prei8 at their lower ends threaded to receive right ferred embodiment, a considerable freedom of and left threaded rotatable adjustable connecmovement of the ends is of decided advantage, in tion 2i! having a central ratchet collar 2l formed that it permits the extreme' ends of the brake with radial openings to receive a tool such asa lining to fully and eiectively engage the drum nail or screw-driver inserted through an open- 20 when the brake is applied. I suggest that the ing in the backing plate. l above object be effected by anchoring' the full According to one feature of my invention, the wrapping brake at both of its ends through the backing platemay be provided Vwith a combined intermediary of links, a single link being placed steady rest and guide means 24, disclosed in Figat each end of the brake. A further and imure and which may comprise an S-shaped 25 portant feature of the invention resides in so constamping having a U- portion 26 defining a chanstructing and positioning the anchor links as to nel receiving the moving web of the friction place the same in a condition of tension when means. The stamping 24 thus functions to guide performing their functionof taking the braking the friction means in its movement about the 30 torque. drum and furthermore obviates lateral movement 30 I further propose to so position the tensioned thereof. anchoring links that the same serve to effectively The shoe I6 is preferably provided with a novel thrust the extreme heel end of the brake into eccentric stop 28 adjustably mounted in the backdrum contact, and inthe brake illustrated each ing plate and operable from outside the backing link is pivoted at one endto a stationary anchor plate and having a stop roller 30 engaging the 35 post and its other and forward end is preferably inner face of the shoe rim. The details of this slotted to receive a thrust pin fixed in the body eccentric stop form no part of the invention of the friction means. Each link is further inclaimed herein, the same being the invention of clined to the horizontal to insure that the friction Ludger E. La Brie described and claimed in his means, such as a band or shoe, will be wedged application No. 304,196, led September 6, 1928. 40 into drum contact, Vfulcrurning about the afore- The shoe I6 may be urged against the adjustable mentioned thrust pin. stop roller 30 of the eccentric 28 when the brake Other features of the invention` relate to reis released, by means such as a spring 32 inclined flnements in a novel cam, which refinements inat such an angle as to act through the connection cludes novelly constructed stops for limiting 20 to urge the shoe I 6 away from the drum. 45 movement of the shoe contacting portion of the Spring 32 also serves to force the web of the shoe cam; to a novel combined guide and steadying into contact with the guide clip 24. means for the friction element of the brake and According to an important feature of the into other desirable details, of construction which vention, the ends of the shoes or their equivalents will be apparent from the following description of are provided with my novel anchoring links 33 50 the illustrative embodiments shown in the acwhich may comprise stampings 34 on either side companying drawing, in Which: 1- of the web of the friction means, which stamp- Figure 1 is avertical section through the brake ings are pivoted at their outer ends to a fixed just inside the head of the brake drum and showpivot post 36 detachably secured to the backing ing the brake in side elevation; plate l2. At their inner or forward ends the 55 stampings, which together form the aforemen-1 tioned link, are preferably longitudinally slotted to receive a pivot pin Sli, which pin is passed through the Web of the friction means having a driving t therewith. The brake is applied by means of a novel cam comprising spaced parallel stampings 40 pivoted at their lower ends to a crank arm @2bn the end of a shaft (not shown) which is journaled in the backing plate. Squareshapedthrust blocks 413 are rotatably mounted on pins 46 mounted in the cam plates 4B. These thrust blocks 44 are slightly concave of face to' receive the rounded ends of the web of the fric-- tion means, all as clearly disclosed Yin Figure l.

According to an important minor feature of the invention, the thrust blocks 44 are prevented from turning to any substantial degree by means of novelly formed stops 138 pressed inwardly by a step punch from the face of the cam plates di] the sheared metal being preferably rectangularly shaped on the inner side by a suitable die. These novelly formed stops y obviate any substantial swivelling movement of the blocks 44 to prevent the corners of the same contacting the rounded ends of the shoes. This construction insures that the concave sides of the blocks will at all times remain in thrust engagement with the ends of the friction means. Y

In operation of the brake the cam is rotated, against the resistance of the spring Eil secured tothe Webs of the shoes,-thrusting the ends of the shoes apart into engagement with the rotating drum. The shoes are, in this movement, guided by the pins 38 moving along the slots in the A link s. Once into drum contact, one or the other ofthe shoes I4 and I6 is wiped around the drum,

the particular shoe which is given this action being determined by the direction of rotation of the drum. The one shoe functions to move the other into drum engagement through the connection 20, the latter shoe, for example I6 Figure 1, moving around the drum until its pin 38 contacts the end of the slot in the link. With further pressure of the applying means and the wiping action of the drum, the link tends to move upwardly from its lower end, as shown in Figure l, anchoring the shoe I6 together with the shoe I4, on the fixed pivot 36. The extreme end of the shoe It is thus wedgingly forced into drum contact, the link 33 taking the braking torque and being placed under a condition of tension. With Vthe drum turning clockwise, shoe iB functions in the same manner as just described with respect to the shoe it. The webs of the shoes i4 and IS are slotted at 52 to permit the aforementioned movement of the shoe and when the brake is released the return spring 5G functions to pull the ends of the shoes together, the tops of the slots 52 contacting the fixed anchors 3G to determine the released position of the shoes.

By this construction I have provided a full wrapping type of brake, whose anchor structure is such Vas to insure that all of the lining area will be forced into full drum contact and this anchor construction furthermore insures that the friction means will be fully released from drum contact. f

While one illustrative embodiment has been described in detail, it is not my intention to limit the scope of the invention to that particular embodiment or otherwise than by the terms of the appended claim.

I claim: l A brake applying device including a thrust member having an arm on which it is pivoted, said arm having a stop holding the thrust member from turning. e

HUMPHREY F. PARKER. 

